The investigation of North Carolina's football program has expanded into possible academic misconduct involving players and a woman who has also worked as a tutor for coach Butch Davis' son.

Robert Willett/The Associated PressFrom left to right, North Carolina Athletic Director Dick Baddour, UNC Chancellor Holden Thorp, and head football coach Butch Davis arrive for a news conference about their football team Thursday in Chapel Hill, N.C.

Athletic Director Dick Baddour, speaking at a news conference Thursday night, declined to identify the players or say how many may be involved. He said there is no timetable for resolution, but "it is likely that the review would extend beyond the start of the season."